1. Field of the Invention
The present invention relates generally to a Bluetooth apparatus and method for a portable terminal. More particularly, the present invention relates to an apparatus and method for switching a call to a peripheral Bluetooth device in a portable terminal and detecting a peripheral Bluetooth device to which a user desires to switch a call.
2. Description of the Related Art
The use of portable terminals is rapidly increasing due to their portability and increasing functionality. Service providers (terminal manufacturers) of mobile terminals are competitively developing more convenient functions in order to attract more users.
For example, the portable terminals provide various functions such as a phone book, a game, a scheduling management function, a Short Message Service (SMS), a Multimedia Message Service (MMS), a Broadcast Message Service (BMS), an Internet service, an Electronic mail (E-mail) service, a morning call, a MP3 (MPEG Audio Layer-3), digital camera and a wide variety of services not mentioned above.
Portable terminals also provide various services such as headset, music, printing and file transmission by a Bluetooth function among the near field communication technologies have recently been launched.
Bluetooth uses 2.4 GHz band frequency of ISM (Industrial Scientific Medical) band to define wireless communication between various terminals and Bluetooth devices. If there is another peripheral Bluetooth device, a host device searches an available Bluetooth device through a Host Controller Interface (HCI) inquiry and receives information about an available service (e.g., information about a profile of the Bluetooth device) through an HCI response signal of the searched Bluetooth device.
The profile of a Bluetooth device is a definition of the arrangement of protocols for protocol applications, and includes a set of commands set to drive a Bluetooth device according to a service provided by the Bluetooth device. The profile of the Bluetooth device varies depending on the applications used, and a typical example of the profile is a Handsfree Profile (HF). In the handsfree profile, Bluetooth devices may be classified into a handsfree (HF) device and an audio gate (AG) device.
The hands free profile includes a headset profile (HSP). The HF device may be a mono/stereo headset or a handsfree device, and the AG device may be a portable terminal. The HF device and the AG device perform Bluetooth communication when a Service Link Connection (SLC) is connected therebetween.
The Bluetooth technology supports both data communication (such as voice and audio) that is sensitive to a delay time and high-rate data communication (such as packet data) that is less sensitive to a delay time. Two links are defined between Bluetooth devices for this type of communication. One of the two links is a Synchronous Connection-Oriented (SCO) link for voice data communication, and the other is an Asynchronous Connection-Less (ACLO link for packet data communication.
The Bluetooth technology provides three SCO channels and seven ACL channels between a master device requesting Bluetooth communication and slave devices receiving the request. However, if an SLC link is connected between Bluetooth devices (i.e., between a master and a slave) to perform communication, the connected SLC link must be released to connect an SLC link and performs communication with another device.
More particularly, without a disconnection request of the AG device and the HF device, one HF device cannot selectively connect a service and an SCO channel with respect to a plurality of AG devices. Also, one AG device cannot selectively connect a service and an SCO channel with respect to a plurality of HG devices.
Therefore, what is required is an apparatus and method for connecting with another HF device without disconnecting a service link during the performance of Bluetooth communication.